I read recently about a "Gorge Trail" that connects downtown Ithaca, Buttermilk Falls State Park, Robert Tremen State Park and Taughannock State Park. I have yet to find any maps of the route under this name. I did find a bit about the Black Diamond Trail, which is probably the same trail:

Day 2 of our Finger Lakes tour is going to be seeing the parks around Ithaca and then heading up to Taughannock. The road route looks fine, but I got curious about a trail system that connected 3 of the parks we'd be visiting.